He grabbed at a protrusion of rock with his right hand.他用右手抓住了一块凸起的岩石。A similar rocky protrusion was noticed in the north apse.在北侧半圆壁龛另有一块相似的石头.But the retrusion of alveolar mandible led to chin protrusion.前颅底和下颌骨发育正常,而下...